Ambulacra of C. subdepressus juveniles.

A Oral view of a juvenile showing the distribution of podial types within ambulacral zones (I–V in white circles); bbaba for type I and aabab for type II. The middle section of interambulacra are marked with dashed white lines. B Detail of ambulacrum I of a juvenile during the resorption of larval tissues. Dashed white circles mark the position of the first two podia. Type I originated on the ambulacral column Ib on the peristome edge and was not encircled by the skeleton; type II emerged from a pore in the skeleton on the ambulacral column Ia. C Ambulacrum I of a 2 months old juvenile still showing the same pattern of the younger juvenile in B. Scale bars =  (A); (B, C)